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By 1946international - Last Year
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Before I swap in my rebuilt 292 into my '30 Model A Tudor should I reconsider the camshaft that is in it? The car is a Model A with a '48 Ford banjo rear with 3.73 gears and 750X16 tires. The motor has stock style pistons 0.40 " oversize and "G" heads, offenhauser 3 two intake with three 94's. I'm a little concerned that the exhaust opens late compared to some other cams and just don't want to be disappointed once it is in the car.
The camshaft in the rebuilt motor is a new Comp Cam unit with:
.471" Gross lift both intake & exhaust
at .050" lift intake opens at 4* BTDC closes at 40* ABDC
at .050" lift exhaust opens at 43* BBDC closes at 7* ATDC
Duration @ .050" intake, 224* exhaust 230*
lobe lift , .3140 both intake & exhaust
lobe separation 108*
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By Joe-JDC - Last Year
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My personal experience with a Comp Cams camshaft was that they ground it using the wrong angle for the lifter bore, and it would only work installed straight up, no advancing or retarding to make it work better. Every cylinder was off when degreeing the camshaft, and I had to send it back to Comp. I have not had any problems with Isky performance camshafts. Just my experience, but I also do not like the Offenhauser 3x2 intake manifold for anything over stock performance camshafts. Check out Ted's site for dyno tests on the different 3x2 intakes and carburetors. I call it the "Awfulhauser" intake. Joe-JDC
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By 55blacktie - Last Year
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1946, just going by the numbers, your cam and induction system won't be the best combination, but you should be able to live with it. With a 108 LSA and more exhaust duration, I'm assuming you want people to know it's cammed while idling. hopefully, you don't have power brakes. Although the 3 x2s look impressive, a good intake and single 4-barrel will give better results and be easier to live with.
Other than knowing my uncle blew a couple of rearends in his 51 Flatty, I don't know much about the 48 banjo. Being in a light car will help. Automatic/stick? Your tires will most likely spin, rather than hook up, which will help. Just my 2 cents.
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By charliemccraney - Last Year
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I would reconsider it because f the issues Joe states. I think the specs should be ok. It should sound good and perform well when the rest of the engine is matched to it. It's hard to suggest a cam because what one person fines tolerable is intolerable to another and what one considers enough power is too little for another.
I would definitely reconsider the intake. Links to mentioned articles:
https://www.eatonbalancing.com/2013/12/18/y-block-ford-3x2-intake-testing/
https://www.eatonbalancing.com/wp-content/uploads/2020/10/YBlock-146-Craine-3X2-Test.pdf
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By 1946international - Last Year
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Yes, I read the info on this intake and know it is a poor performer, I knew it when I bought it but it came with the carbs and was just under $200, so that is what I have. I am however on the look out for a better intake.
With all that said,  This is a cam that Ted recommends, you can see (if I loaded it correctly) that the Isky came opens the exhaust 10* sooner and the intake 4* sooner. This is my concern and I'm thinking about swapping it while the motor is still on the stand and I can roll it over.
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By cos - Last Year
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Hello 1946 If I read specs right, I just order that cam ( Teds advice) for a 292 rebuild. I have a original EDB-D cam but wanted a more modern version. Was concerned with depth of oil grove in center journal . Call Isky back and ask, (Nolan) said no problem same a depth as Fords stock cams. Ask if it could be cut a little deeper, said no they don't do this. Guess when I get it will see. Not a big deal but a nuisance. I have had in the pasted, had Oregon cams grind a EDB-D cam, claim to have a original for pattern. Thinking center grove was deeper than stock.
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By Deyomatic - Last Year
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Boy...not to hijack the post, but unless I am missing something, ISKY has about the worst website I've ever seen. No mention of engine "family," no mention of displacements...
I put in 1959 Fairlane just to see what was available and it was showing me HYDRAULIC lifters...I can only guess that's for an early FE.
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By Joe-JDC - Last Year
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Check out Summit Racing, they have 3 listings for Howards Camshafts, and 4 for Isky for the 292/312 Ford Y Block. However, the stock is very limited at this point with wait time for shipping some of the camshafts for January 2024. Joe-JDC
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By 55blacktie - Last Year
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Ted Eaton (eatonbalancing.com) will tell you everything you want to know (and then some) about Isky Y-block cams and will recommend a grind for your application. Your choices aren't limited to off-the-shelf cams.
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By Ted - Last Year
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1946international (11/28/2023)
... With all that said, This is a cam that Ted recommends, you can see (if I loaded it correctly) that the Isky came opens the exhaust 10* sooner and the intake 4* sooner. This is my concern and I'm thinking about swapping it while the motor is still on the stand and I can roll it over.
To accurately compare the camshafts, the advertised duration numbers are also required. Looking at just the 0.050” values does not give an accurate picture of how the lifter is beginning its initial rise on the lobes and the decline off the lobes. The advertised camshaft numbers are typically at 0.020” lifter rise for a solid lifter camshaft. The 0.020" values are used for dynamic compression ratio calculations as well as giving a snapshot of what the lobe ramps look like at the start and end of the lifter travel when comparing the 0.020” and the 0.050” values against each other.
As Joe mentions, there have been a number of quality issues with the Comp Cams grinds. Top of the list are the lobes being ground on the wrong lifter bank angles and second on the list is the variability of the lobes in regard to the camshaft lobes being ground the same for all the cylinders. When degreeing in the camshaft, always check both the intake and exhaust lobes on at least one cylinder on each bank to ensure that the camshaft is ground the same for both banks. Cylinders 1 & 6 both share the same TDC on the degree wheel so it’s just a matter of moving the dial indicator to do that. Any variability in those two cylinders will suggest that the camshaft was ground with the incorrect lifter bank angle. If variability is found, then it may be necessary to check all sixteen lobes for verification of that.
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By Ted - Last Year
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Deyomatic (11/28/2023)
Boy...not to hijack the post, but unless I am missing something, ISKY has about the worst website I've ever seen. No mention of engine "family," no mention of displacements...
I put in 1959 Fairlane just to see what was available and it was showing me HYDRAULIC lifters...I can only guess that's for an early FE.
I still have the old school paper catalogs. Upon going to the Isky website and pulling up their web catalog version, the Ford Y camshafts will be on page 134. Just like my paper catalog, there are only four camshafts listed. I did take a quick look at their website in general and doing the search by car and year did not do much good for a Y camshaft. However, looking up the Y camshaft by using the “Search Engine” icon did bring up the Y camshafts by selecting the appropriate make and engine.
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By 1946international - Last Year
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Thank you all for bringing up the issue with the Comp Cams cam being ground incorrectly, I do remember checking both banks when I installed this cam. My main concern is if this Comp Cam is a good one to use or if I should get a different one and install it before I install the engine.
I don't have any other info on lobe profile so can't do any more of a detailed comparison.
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By Ted - Last Year
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1946international (11/27/2023)
The camshaft in the rebuilt motor is a new Comp Cam unit with:
.471" Gross lift both intake & exhaust
at .050" lift intake opens at 4* BTDC closes at 40* ABDC
at .050" lift exhaust opens at 43* BBDC closes at 7* ATDC
Duration @ .050" intake, 224* exhaust 230*
lobe lift , .3140 both intake & exhaust
lobe separation 108*
Based on the provided specs, the camshaft will be a good driver assuming you get those three carburetors working as they should. With the 108° lobe centerline, it will have a ‘rumpy’ idle. Based on the 0.050” numbers, it is ground straight up so I would recommend that it be installed with at least 4° advance (104° intake lobe centerline).
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By 1946international - Last Year
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I think when I installed it, I put it at 2* advanced but can change that.
Thanks for your input. I have just been worried about that "late" opening exhaust valve.
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By Ted - Last Year
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1946international (12/1/2023)
...Thanks for your input. I have just been worried about that "late" opening exhaust valve.
You do need the advertised duration numbers to determine if the exhaust value is indeed opening later on your camshaft. The 0.050” numbers may be misleading as the valve itself actually started to open somewhere around the 0.020” valve lash value.
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By 1946international - Last Year
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checked the cam card, would the "duration @ .015 tappet lift " be what you need? it is listed at 261* for intake and 267* for exhaust
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By Ted - Last Year
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1946international (12/3/2023)
Checked the cam card, would the "duration @ .015 tappet lift " be what you need? it is listed at 261* for intake and 267* for exhaust
The 261° and 267° numbers would be the advertised duration while the 0.015” number is likely the recommended valve lash setting. Setting the valve lash at 0.020” would reduce both of those numbers. Assuming the camshaft lobes are symmetrical in nature and based on the 0.050” numbers being the installed straight up values (no advance / no retard) then I get the following open/closed numbers for 0.015” lash.
Intake open 22½° BTDC
Intake close 58½° ABDC
Exhaust open 61½° BTDC
Exhaust close 25½° ATDC
A later closing of the exhaust valve can be a result of the camshaft being ground on 108° lobe centers versus a cam that’s ground on a wider lobe centerline. That in combination with the earlier opening of the intake valve that occurs with the 108° lobe centers increases the amount of valve overlap which in turn gives that ‘rumpier’ sound but at the expense of some manifold vacuum and a reduced signal to the carburetor.
Something else to watch for on camshafts is if the camshaft is ground straight up or with a given amount of cam advance or retard built in. I typically specify 2° of cam advance (4° crankshaft degrees) built into the Isky camshafts I order. If trying to compare that to a camshaft that’s ground straight up versus one that’s not, then that must be taken into account. I noticed that the camshaft you listed is ground ‘straight up’.
If wanting to close the exhaust valve earlier, then just increase the exhaust valve lash. If also trying to smooth out the idle and/or increase the manifold vacuum, then also increase the intake valve lash.
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By 1946international - Last Year
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Ted, thank you so much for your input and time on this.
So are you still advising to use this cam and install it at 4* advanced?
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By Ted - Last Year
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1946international (12/5/2023)
...So are you still advising to use this cam and install it at 4* advanced?
That’s a Yes. If it's a new timing chain, you will get away with 6° of cam advance. If the 94’s have some difficulty idling with that particular camshaft at 0.015” lash, then just increase the valve lash to 0.020". That will strengthen the vacuum signal to the carbs and in turn provide some additional enrichment control at the idle mixture screws. Switching from the Offenhauser 3X2 intake to a different brand 3X2 intake (Edelbrock, Edmunds, Fenton, Weiand) will also have a positive effect on the idle signal.
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By 1946international - Last Year
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Great, The car runs very good on those carbs, idle is dependable at around 850 t0 900 rpm and throttle response off idle is very good. The only problem is just when the secondaries open it stumbles a little. If you open the secondaries slowly it will not stumble. I'm running accelerator pumps on all carbs with the link rod on the secondaries lengthened to get full advantage of pump stroke on those carbs. Also running power valves in all three, 6.5" valves I guess as they are the ones that came in the rebuild kits. The secondaries also have the stock base with the idle circuits but the idle screws are screwed in all the way. Remember this is using the progressive linkage.
With all that being said, the "B" manifold and 1850 performed way better at full throttle, but I bet that is due to that Offenhauser manifold that is on the motor now.
Thanks for your input on the cam, I'm sure you get tired of going through cam stuff all the time. Oh, yes the timing chain is new, never run.
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By 55blacktie - Last Year
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850-900 rpm idle is too high. Do you have trouble with run-on once the ignition is turned off?
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By miker - Last Year
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Depends on the engine. My street driven F code clone with a longer cam idles at 1000. No run on.
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By 1946international - Last Year
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No run on at all
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